On the nature of the control by RC gene in E. coli: Amino acid-dependent control of lipid synthesis

Sokawa, Yoshihiro; Nakao, Eiko; Kaziro, Yoshito

doi:10.1016/0006-291x(68)90263-5

Cited by 94 publications

(45 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Membrane phospholipid synthesis in E. coli is also inhibited during the stringent response (23). We have recently shown that the ␤-lactam-induced bacteriolysis of amino acid-deprived bacteria resulting from the relaxation of the stringent response is dependent on ongoing phospholipid synthesis; i.e., the inhibition of relaxed phospholipid synthesis results in penicillin tolerance (21).…”

mentioning

confidence: 99%

Direct correlation between overproduction of guanosine 3',5'-bispyrophosphate (ppGpp) and penicillin tolerance in Escherichia coli

Rodionov

Ishiguro

1995

J Bacteriol

View full text Add to dashboard Cite

The penicillin tolerance exhibited by amino acid-deprived Escherichia coli has been previously proposed to be a consequence of the stringent response. Evidence indicating that penicillin tolerance is directly attributable to guanosine 3 ,5 -bispyrophosphate (ppGpp) overproduction and not to some other effect of amino acid deprivation is now presented. Accumulation of ppGpp in the absence of amino acid deprivation was achieved by the controlled overexpression of the cloned relA gene, which encodes ppGpp synthetase I. The overproduction of ppGpp resulted in the inhibition of both peptidoglycan and phospholipid synthesis and in penicillin tolerance. The minimum concentration of ppGpp required to establish these phenomena was determined to be 870 pmol per mg (dry weight) of cells. This represented about 70% of the maximum level of ppGpp accumulated during the stringent response. Penicillin tolerance and the inhibition of peptidoglycan synthesis were both suppressed when ppGpp accumulation was prevented by treatment with chloramphenicol, an inhibitor of ppGpp synthetase I activation. Glycerol-3-phosphate acyltransferase, the product of plsB, was recently identified as the main site of ppGpp inhibition in phospholipid synthesis (R. J. Heath, S. Jackowski, and C. O. Rock, J. Biol. Chem. 269:26584-26590, 1994). The overexpression of the cloned plsB gene reversed the penicillin tolerance conferred by ppGpp accumulation. This result supports previous observations indicating that the membrane-associated events in peptidoglycan metabolism were dependent on ongoing phospholipid synthesis. Interestingly, treatment with ␤-lactam antibiotics by itself induced ppGpp accumulation, but the maximum levels attained were insufficient to confer penicillin tolerance.In Escherichia coli, amino acid deprivation results in the coordinate inhibition of a variety of metabolic activities. This phenomenon, known as the stringent response, probably represents a means of enhancing the survival of bacteria during periods of starvation (see reference 4 for a review). Amino acid-deprived E. coli rapidly accumulate guanosine 3Ј,5Ј-bispyrophosphate (ppGpp). The stringent response is thought to be mediated by ppGpp. The synthesis of ppGpp during the stringent response is catalyzed by ppGpp synthetase I, a ribosomeassociated enzyme encoded by the relA gene, which is activated by amino acid starvation. The stringent response can be prevented (i.e., relaxed) by inhibiting the synthesis of ppGpp. This may be accomplished either by introducing a mutation in the relA gene or by treating amino acid-deprived relA ϩ bacteria with certain ribosome inhibitors, e.g., chloramphenicol, which apparently interfere with the activation of RelA.The intracellular levels of ppGpp in E. coli are inversely related to growth rate (22). The growth rate-dependent synthesis of ppGpp is catalyzed by ppGpp synthetase II, which has been identified as the product of the spoT gene (9, 29).Cell wall peptidoglycan metabolism is inhibited during the stringent response. One key site of...

show abstract

mentioning

confidence: 99%

Direct correlation between overproduction of guanosine 3',5'-bispyrophosphate (ppGpp) and penicillin tolerance in Escherichia coli

Rodionov

Ishiguro

1995

J Bacteriol

View full text Add to dashboard Cite

show abstract

“…1 and 2). It has been proposed that (p)ppGpp functions as a pluripotent regulator molecule that controls a number of biosynthetic and catabolic pathways; it restricts synthesis of stable RNA (3), of purine nucleotides (4), of glycolytic esters (5), and of phospholipids (6).In order to elucidate the function of (p)ppGpp as a major regulator molecule in bacterial cells, it is essential to understand the precise mechanism of its synthesis and degradation as well. The mode of synthesis of (p)ppGpp has been discovered by Haseltine et al (7) who showed that these compounds are synthesized on ribosomes by an enzyme named "stringent factor."…”

mentioning

confidence: 99%

mentioning

confidence: 99%

Mechanism of the in vitro breakdown of guanosine 5'-diphosphate 3'-diphosphate in Escherichia coli.

Heinemeyer¹,

Richter²

1978

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Degradation of guanosine tetraphosphate (ppGpp) involves an enzyme associated with the ribosomal fraction from spoT'strains of Escheric4ia coli. Double Auxotrophic strains of Escherichia coli are known to accumulate rapidly the unusual nucleotides guanosine 5'-diphosphate 3'-diphosphate (ppGpp) and guanosine 5'-triphosphate 3'-diphosphate (pppGpp) when deprived of an essential amino acid (for reviews, see refs. 1 and 2). It has been proposed that (p)ppGpp functions as a pluripotent regulator molecule that controls a number of biosynthetic and catabolic pathways; it restricts synthesis of stable RNA (3), of purine nucleotides (4), of glycolytic esters (5), and of phospholipids (6).In order to elucidate the function of (p)ppGpp as a major regulator molecule in bacterial cells, it is essential to understand the precise mechanism of its synthesis and degradation as well. The mode of synthesis of (p)ppGpp has been discovered by Haseltine et al. (7) who showed that these compounds are synthesized on ribosomes by an enzyme named "stringent factor." Despite attempts by a number of groups, the mechanism of ppGpp breakdown has remained unresolved until recently (8, 9). Although, in vivo, ppGpp is rapidly degraded when E. coli cells are resupplemented with the lacking amino acid (10), attempts to demonstrate degradation in vitro have failed (11)(12)(13)(14)(15). Genetic studies have shown that in vivo breakdown of ppGpp is associated with the spoT+ allele; in spoTmutants, ppGpp breakdown is significantly slower than in wild-type strains (16,17). This may indicate that spoT-mutants either have a similar but less active degradation device or utilize an alternative pathway. The enzyme involved and the mechanism of ppGpp breakdown are the subject of this communication. MATERIALS AND METHODSThe ppGpp degrading enzyme was prepared from the stringent E. coli strains CGSC 2834/a (relA +) and CP78 (relA +, CCA+, his-, leu-, arg-, thr-, B1-) or from the relaxed strain CP79 (relA-, CCA-, his-, leu-, arg-, thr-, BR -); CP78 and CP79 were kindly provided by M. Deutscher (Farmington, CT); K10 (spoT-, relA-, tonA22) were from A. Bock (Regensburg, Germany). [8-3H]GTP (New England Nuclear, Boston, MA) was used for preparation of pp[3H]Gpp (specific activity, 2

show abstract

“…In a glycerol auxotroph of Staphylococcus aureus lysylphosphatidylglycerol increased in the absence of glycerol (9). Alterations in the pattern of phospholipids were also reported under various growth conditions or at various growth phases (10)(11)(12)(13)(14)(15)(16). Phage infection in E. coli also induced cardiolipin accumulation (17).…”

mentioning

confidence: 99%

“…For example, the accumulation of cardiolipin has been observed under various conditions, as a consequence of either the death of the cells or the ceasing of cell growth (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). Incubation of the cells with various drugs such as phenethyl alcohol (1), penicillin or chloramphenicol (2), levorphanol (3), or without the addition of carbon source (4), increased cardiolipin content in the cells.…”

mentioning

confidence: 99%

Effect of Glycine on Phospholipid Metabolism in Bacillus Subtilis

Sato

Okuda

Izaki

et al. 1974

J. Gen. Appl. Microbiol.

View full text Add to dashboard Cite

Effect of glycine on the metabolism of phospholipid in Bacillus subtilis 6169 was studied. Cell lysis and an alteration of phospholipid metabolism were observed when the cells were grown in the presence of 1 of glycine. Under these conditions, cardiolipin content increased from 20 to 60 % with concomitant decrease in phosphatidylglycerol from 60 to 15 % of the total phospholipid-phosphorus.The incorporation of 32P-orthophosphate and 3H-glycerol into phospholipids also showed that glycine did not inhibit the synthesis of phosphatidylglycerol but presumably stimulated the conversion of phosphatidylglycerol to cardiolipin. Addition of a small amount of glycerol with glycine to the culture medium significantly suppressed the cell lysis and the change in the phospholipid metabolism. The possible mechanism, by which phospholipid metabolism was altered, was discussed.

show abstract

On the nature of the control by RC gene in E. coli: Amino acid-dependent control of lipid synthesis

Cited by 94 publications

References 6 publications

Direct correlation between overproduction of guanosine 3',5'-bispyrophosphate (ppGpp) and penicillin tolerance in Escherichia coli

Direct correlation between overproduction of guanosine 3',5'-bispyrophosphate (ppGpp) and penicillin tolerance in Escherichia coli

Mechanism of the in vitro breakdown of guanosine 5'-diphosphate 3'-diphosphate in Escherichia coli.

Effect of Glycine on Phospholipid Metabolism in Bacillus Subtilis

Contact Info

Product

Resources

About